Main-spring releasing accessory for firearms

ABSTRACT

A DEVICE FOR RELEASING THE TENSION OF THE MAIN-SPRING OF A FIREARM WITHOUT BECOMING A CAPTIVE PART THEREOF.

Feb. 23., 1971 E, E. MccoNNl-:LL 3,564,745

K MAIN-SPRING RELEASING AccEssoRY FOR FIREARMS l Filed'uarch 2a, 1969" l/,oo

INVEINTORz ELBERT E. MCCONNELL irlUnited States Patent Of 3,564,746 Patented Feb. 23, 1971 3,564,746 MAIN-SPRING RELEASING ACCESSORY FOR FIREARMS Elbert E. McConnell, 80 Church St., Merrimac, Mass. 01860 Filed Mar. 28, 1969, Ser. No. 811,355 Int. Cl. F41c 27/ 00 U.S. Cl. 42-1 6 Claims ABSTRACT F THE DISCLOSURE A device for releasing the tension of the main-spring of a firearm without becoming a captive part thereof.

BACKGROUND OF INVENTION When the action of a hammerless firearm, for example a hammerless double barreled shotgun is closed after cleaning, the mainspring, or mainsprings, remain cocked, i.e., under compression.

In order to release the tension of these springs, without allowing the firing pins to fall free and invite damage, the usual method is to employ a so called snap cap.

The snap cap resembles a shell and has a springloaded plunger in place of the primer to cushion the fall of the firing pin. The snap cap becomes a captive part of the respective arm, and it must be provided for each barrel, and a set for each double barreled shotgun. Moreover, an obstruction is left in the barrel which must be removed before the arm can be used. Such an obstruction restricts the free flow of air and invites the formation of rust under unfavorable conditions.

The device according to this invention serves the same purpose as a snap cap, but is not subject to the limitations of such a cap.

SUMMARY OF INVENTION A device for releasing the tension of the main spring of a firearm having a relatively long barrel such as a shotgun or rie includes a rod-shaped member defining a hollow chamber adjacent one end thereof. The aforementioned rod-shaped member is free from any radially outward projection at the preponderant portion of the length thereof adjacent to said hollow chamber to allow insertion of the hollow-chamber-defining end of said member into the barrel of a firearm from the muzzle end thereof and movement of said hollow-chamber-defining end to the breech region thereof. The hollow chamber defined by said rod-shaped member houses a springbiased plunger having an axially outer end surface accessible from the outside of said member.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is an axial section of the plunger end of a device embodying this invention;

FIG. '2 is an exterior view of the device shown in FIG. 1 broken near its middle portion;

FIG. 3 is an end view of FIG. 2;

FIG. 4 is an axial section similar to FIG. 1 of another device embodying this invention and being of simplified construction; and

FIG. is an isometric view of a device embodying this invention inserted into the barrel of a double barreled shotgun, which is shown in phantom.

DESCRIPTION OF PREFERRED EMBODIMENTS Referring now to the drawings, and particularly to FIGS. 1 and 2 thereof, numeral 1 has been applied to indicate a rod-shaped member, preferably in the shape of a tubular casing of aluminum alloy or a similar material.

A metal disc 2 which is held in place by a plurality of transverse pins 3 forms an abutment for the left end of spring 4. Helical spring 4 is of proper size to provide the right cushioning action for plunger 5, which is preferably of synthetic resin and cylindrical. Plunger 5 is constructed so that it may be reversed, i.e., it has two axially outer portions of reduced diameter of which either may form a retaining shoulder 6 for spring 4, and of which either portion has a firing pin-obstructing end surface. Both ends of plunger 5 have a slight spherical radius to insure proper contact at the breech of the firearm. A screw threaded cap 7 is aflixed to the right end of casing 1 to retain the plunger 5 therein. Cap 7 is so designed that it may be removed to reverse plunger 5, should one end of plunger 5 become worn out by repeated use.

Referring now specifically to FIG. 2, a knurl 8 has been applied to the muzzle end of rod-shaped casing 1 to aid in holding it during use.

Referring now to FIG. 4, a tube 1' with a relatively thin wall is used as a casing and a construction 11 is formed by rolling or crimping to support a sheet metal disc, a helical spring 4' cushions a non-reversible plunger 10, preferably of a synthetic resin and also formed with a slight spherical radius. The plunger 10 is retained inside tube 1 by a constriction at the right end of tu'be 1' formed by rolling or crimping that end of tube 1.

Referring now to FIG. 5, the main spring tension releasing device is shown inserted into the left barrel of a double barreled shotgun with the plunger end of the rod held firmly against the 'breech of the gun. The trigger which fires the left barrel may now be pulled and the firing pin will fall, the firing pin being protected from free fall and possible damage by the resin plungers 5 and 10 shown in FIGS. 1 4. Since the device must pass through the choke of a shotgun barrel, it must necessarily be of smaller diameter than the chamber, on the other hand the diameter of the plunger must be so large that the greatest possible amount of misalignment will still result in a portion of the plunger being under the firing pin and in contact with the breech of the arm. The plunger is also relatively long so that should the firing pin strike the plunger at some point other than the center, it will not cause the plunger to bind. The length of a rifle barrel is 16'l min. and that of a shotgun usually 32 max. Therefore the length of rod 1 should be inthe order of 20-36 inches.

It will be understood that this description of my invention is intended to be illustrative rather than limiting, as the invention may be variously embodied, and is to be interpreted as claimed.

I claim as my invention:

1. A device for releasing the tension of the main spring of a firearm having a relatively long barrel such as a shotr gun or rifle, said device including -(a) a rod-shaped member defining a hollow chamber adjacent one end thereof, said member being free from any radially outward projection at the preponderant portion of the length thereof adjacent said hollow chamber to allow insertion of the hollowchamber-defining end of said member into the barrel of a firearm from the muzzle end thereof and movement of said hollow-chamber-detining end to the breech region thereof; and

(b) said hollow chamber housing a spring-biased plunger having an axially outer end surface accessible from the outside of said member.

2. A device as specified in claim 1 wherein said rodshaped member has a length in the order from 20 to 36 inches.

3. A device as specified in claim 1 wherein said rodshaped member is of metal and said plunger of a synthetic resin.

4. A device as specified in claim 1 wherein said plunger includes a center portion of relatively large diameter and axially outer portions of relatively small diameter and wherein the axially outer end of said hollow chamber is closed by a center-perforated cap being readily removable from and alixable to said rod-shaped member, one of said axially outer portions of said plunger projecting into a plunger biasing helical spring and the other of said axially outer portions of said plunger projecting into the center perforation of said cap.

5. A device as specified in claim 1 wherein said rodshaped member is tubular.

6. A device as specified in claim 5 wherein said rodshaped tubular member is constricted radially inwardly at a first point spaced from one end thereof, the constriction of said member at said rst point forming an abut- 4 ment Vfor a helical plunger-biasing spring, and wherein said rod-shaped tubular member is constricted radially inwardly at a second point coextensive with the end thereof, the constriction at said second point forming an abutment for said plunger precluding ejection of said plunger from said hollow chamber under the action of said plunger- *biasing spring.

References Cited UNITED STATES PATENTS 2,763,081 9/1956 Huckabee 42-1 (N) 3,382,596 5/1968 Rockwood 42-1 (N) FOREIGN PATENTS 596,261 12/1947 Great Britain 42-1(N) BENJAMIN A. BORCH'ELT, Primary Examiner C. T. JORDAN, Assistant Examiner 

